U.S. patent application number 13/748637 was filed with the patent office on 2013-09-05 for process for making absorbent component.
This patent application is currently assigned to THE PROCTER & GAMBLE COMPANY. The applicant listed for this patent is THE PROCTER & GAMBLE COMPANY. Invention is credited to Steven Lee Barnholtz, Gina Isoldi, Florian Philip Rousselange, Dirk Saevecke, Anirudh Singh, Timothy Duane Smith, Norbert Matthias Stelzer, Christopher Michael Young.
Application Number | 20130228948 13/748637 |
Document ID | / |
Family ID | 47741257 |
Filed Date | 2013-09-05 |
United States Patent
Application |
20130228948 |
Kind Code |
A1 |
Singh; Anirudh ; et
al. |
September 5, 2013 |
PROCESS FOR MAKING ABSORBENT COMPONENT
Abstract
A process for making an absorbent component comprising the steps
of providing individual sheets of pulp; attaching a first
individual pulp sheet to one or more second individual pulp sheets
to form a strip of pulp; feeding the strip of pulp into a
defiberizer; defiberizing the strip of pulp to form defiberized
fibers; and depositing the defiberized fibers onto a forming
surface to form the absorbent component.
Inventors: |
Singh; Anirudh; (Cincinnati,
OH) ; Young; Christopher Michael; (Loveland, OH)
; Smith; Timothy Duane; (Cincinnati, OH) ;
Barnholtz; Steven Lee; (West Chester, OH) ; Saevecke;
Dirk; (Wiesbaden, DE) ; Isoldi; Gina;
(Brussels, BE) ; Rousselange; Florian Philip;
(Neu-Isenburg, DE) ; Stelzer; Norbert Matthias;
(Idstein, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
THE PROCTER & GAMBLE COMPANY |
Cincinnati |
OH |
US |
|
|
Assignee: |
THE PROCTER & GAMBLE
COMPANY
Cincinnati
OH
|
Family ID: |
47741257 |
Appl. No.: |
13/748637 |
Filed: |
January 24, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61606533 |
Mar 5, 2012 |
|
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|
Current U.S.
Class: |
264/103 ;
264/115 |
Current CPC
Class: |
D21H 11/16 20130101;
D21H 15/04 20130101; D21H 11/18 20130101; D21H 15/02 20130101; D21C
9/007 20130101; A61F 13/15617 20130101 |
Class at
Publication: |
264/103 ;
264/115 |
International
Class: |
A61F 13/15 20060101
A61F013/15 |
Claims
1. A process for making an absorbent component, the process
comprising the steps of: providing individual sheets of pulp;
attaching a first individual pulp sheet to one or more second
individual pulp sheets to form a strip of pulp; feeding the strip
of pulp into a defiberizer; defiberizing the strip of pulp to form
defiberized fibers; and depositing the defiberized fibers onto a
forming surface to form the absorbent component.
2. The process for making an absorbent component of claim 1,
wherein the process further comprises the step of positioning at
least a portion of the first individual pulp sheet in contact with
at least a portion of at least one of the one or more second
individual pulp sheets.
3. The process for making an absorbent component of claim 2,
wherein the step of positioning comprises abutting at least a
portion of the first individual pulp sheet to at least a portion of
at least one of the one or more second individual pulp sheets.
4. The process for making an absorbent component of claim 2,
wherein the step of positioning comprises overlapping at least a
portion of the first individual pulp sheet with at least a portion
of at least one of the one or more second individual pulp
sheets.
5. The process for making an absorbent component of claim 1,
wherein the step of attaching comprises mechanically attaching the
first individual pulp sheet to at least one of the one or more
second individual pulp sheets.
6. The process for making an absorbent component of claim 5,
wherein the step of mechanically attaching comprises sewing the
first individual pulp sheet to at least one of the one or more
second individual pulp sheets.
7. The process for making an absorbent component of claim 5,
wherein the step of mechanically attaching comprises dovetailing
the first individual pulp sheet to the one or more second
individual pulp sheets.
8. The process for making an absorbent component of claim 5,
wherein the step of mechanically attaching comprises mechanically
entangling the first individual pulp sheet to at least one of the
one or more second individual pulp sheets.
9. The process for making an absorbent component of claim 5,
wherein the step of mechanically attaching comprises needle
punching the first individual pulp sheet to the one or more second
individual pulp sheets, wherein one or more fibers of the first
individual pulp sheet are in contact with one or more fibers of the
one or more second individual pulp sheets.
10. The process for making an absorbent component of claim 5,
wherein the step of mechanically attaching comprises interleaving
the first individual pulp sheet to at least one of the one or more
second individual pulp sheets.
11. The process for making an absorbent component of claim 1,
wherein the step of attaching comprises adhering the first
individual pulp sheet to at least one of the one or more second
individual pulp sheets.
12. The process for making an absorbent component of claim 11,
wherein the step of adhering comprises taping the first individual
pulp sheet to at least one of the one or more second individual
pulp sheets.
13. The process for making an absorbent component of claim 11,
wherein the step of adhering comprises gluing the first individual
pulp sheet to at least one of the one or more second individual
pulp sheets.
14. The process for making an absorbent component of claim 1,
wherein the first individual pulp sheet comprises at least one
edge, wherein the at least one edge is perpendicular to the machine
direction of the defiberizer when feeding the strip of pulp into
the defiberizer.
15. The process for making an absorbent component of claim 1,
wherein the first individual pulp sheet comprises at least one
edge, wherein the at least one edge is at an angle in the range of
about 5 degrees to about 90 degrees to the machine direction of the
defiberizer when feeding the strip of pulp into the
defiberizer.
16. The process for making an absorbent component of claim 1,
wherein the first individual pulp sheet comprises at least one
edge, wherein the at least one edge is substantially parallel to
the machine direction of the defiberizer when feeding the strip of
pulp into the defiberizer.
17. The process for making an absorbent component of claim 1,
wherein the thickness of the first individual pulp sheet is in the
range of from about 0.5 m to about 5 mm.
18. The process for making an absorbent component of claim 1,
wherein the process further comprises the step of removing the
first individual pulp sheet from a stack comprising a plurality of
individual pulp sheets.
19. The process for making an absorbent component of claim 1,
wherein the process further comprises the step of depositing the
first individual pulp sheet on a transfer device, wherein the
transfer device moves the first individual pulp sheet toward the
defiberizer.
20. The process for making an absorbent component of claim 1,
wherein the process further comprises the step of aligning the
first individual pulp sheet on the transfer device, wherein the
first individual pulp sheet comprises a first face and a second
face, wherein the first face is substantially perpendicular to a
plane of the transfer device.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a process for making an
absorbent component from individual pulp sheets.
BACKGROUND OF THE INVENTION
[0002] Pulp fibers are used in the manufacture of many absorbent
components for absorbent articles including, for example, diapers,
feminine products, adult incontinence products, and paper products.
The pulp fibers used to produce these products are supplied as
rolled pulp or bale pulp. Rolled pulp is generally a continuous
roll of a type of pulp known as fluff pulp. In comparison, bale
pulp generally consists of a stack of individual pulp sheets. Two
primary methods exist to process bale pulp and rolled pulp to
obtain the individual fibers generally required to manufacture
fibrous products. One method is an air-laid process where a
defiberizer, such as a hammermill, interacts with the pulp to
separate the individual fibers of the individual sheet or roll of
pulp. The defiberizer exposes the fibers in the pulp while avoiding
clumping and other adverse conditions that may cause apparent
defects in an end product. The separate fibers are suspended in air
and subsequently transferred to a forming surface such that an
embryonic absorbent component is formed. The other method used to
produce absorbent components is a wet-laid process. In a wet-laid
process, pulp, typically in the form of individual sheets of pulp,
is supplied to a device where the pulp is mixed with an aqueous
solution to form a fibrous slurry. The fibrous slurry is then
deposited onto a forming wire or belt such that an absorbent
component is formed.
[0003] Sheet pulp or fluff pulp may be used in both an air-laid
process and a wet-laid process. In air-laid processes, fluff pulp
or rolled pulp has been the primary choice among manufacturers.
Fluff pulp is the preferred material in air-laid processes because
of its structural characteristics, such as a lower moisture content
and more uniform density. In addition, fluff pulp is supplied in
roll form allowing for a continuous strip of pulp to be fed into
the defiberizer without creating any interruption in the
defiberizing process. An interruption is characterized by a break
or inconsistency in laying down fibers on a forming surface.
Avoiding an interruption is important to the quality of products
produced by the process. For the above reasons, manufacturers using
an air-laid process generally choose rolled pulp to produce fibrous
products.
[0004] Further to the above, manufactures have usually avoided
using bale pulp in air-laid processes because of interruptions in
the defiberizing process. When dealing with short, individual
sheets of pulp, it is often the case that one sheet of pulp is
pulled into the defiberizer at a faster rate than a subsequent
sheet of pulp can be fed into the defiberizer. This gap in feeding
sheets of pulp into the defiberizer can create an interruption in
the supply of individual fibers to a forming surface. The resulting
interruption in the defiberization process ultimately may result in
an inconsistent, varied product. Such an interruption in the
production of an absorbent component for an absorbent article could
result in a product having inadequate absorbency or inferior
softness.
[0005] Sheet pulp and rolled pulp are generally made of the same
raw material. Despite this similarity, individual sheets of pulp
offer some advantages over rolled pulp. Sheet pulp is less
expensive than rolled pulp and can be transported and stored more
easily than rolled pulp. The cost difference between rolled pulp
and bale pulp is due in part to the process used to produce bale
pulp, which is a less expensive process than that used to produce
rolled pulp. In addition, bale pulp is produced by a large number
of sources and, therefore, offers manufacturers more choice in
suppliers and the ability to localize supply with the point of
demand. In comparison, fluff pulp is a specialized grade of pulp
that is produced by an expensive processes requiring large costly
machinery. The expense of the equipment itself coupled with the
expense to operate the equipment has resulted in relatively few
suppliers of fluff pulp. As a result, fluff pulp represents a small
percentage of the overall pulp market. Therefore, sheet pulp offers
economic benefits over fluff pulp.
[0006] Due to the benefits of using bale pulp, processes for
defiberizing individual sheets of pulp have been developed to try
to combat the problem of fiber interruption. For example,
defiberizers have been developed for accepting numerous unattached
sheets of pulp that have been laid against of one another; that is
numerous sheets of pulp in shingled relation enter the defiberizer
at one time. Another apparatus has been developed to defiberize a
pulp sheet with two defiberizing mechanisms in angled relation so
that the force exerted on the pulp sheet is not parallel to the
machine direction, and the feed of the pulp sheet can be controlled
more easily. Still another apparatus that has been developed shreds
the sheets of pulp and stores the shredded pulp in a hopper to
create a uniform supply of shredded pulp for defiberization.
Another method involves folding the sheets of pulp, where the fold
line is parallel to the machine direction, to create a sheet of
uniform thickness to be fed into the defiberizer. Generally, the
above-discussed processes keep the sheets of pulp essentially
separate from one another, which could still result in an
interruption of fibers. In other words, the individual sheets of
pulp in the existing processes are not attached to one another.
[0007] Accordingly, there is a need for a process that is capable
of transforming individual sheets of pulp into a strip of pulp that
simulates a continuous roll of pulp being fed into a defiberizer to
form an absorbent component.
SUMMARY OF THE INVENTION
[0008] The present disclosure fulfills the need described above by
providing a process for making an absorbent component, the process
comprising the steps of providing individual sheets of pulp;
attaching a first individual pulp sheet to one or more second
individual pulp sheets to form a strip of pulp; feeding the strip
of pulp into a defiberizer; defiberizing the strip of pulp to form
defiberized fibers; and depositing the defiberized fibers onto a
forming surface to form the absorbent component.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a schematic, side view of an example embodiment of
a process of the present invention;
[0010] FIG. 2A is a schematic, side view of an example embodiment
of a stack of individual pulp sheets;
[0011] FIG. 2B is a schematic, side view of another example
embodiment of a stack of individual pulp sheets;
[0012] FIG. 2C is a schematic, side view of another example
embodiment of a stack of individual pulp sheets;
[0013] FIG. 3 is a schematic, perspective representation of an
example embodiment of an individual pulp sheet;
[0014] FIG. 4A is a schematic, top view of an example embodiment of
a strip of pulp;
[0015] FIG. 4B is a side view of the strip of pulp of FIG. 4A;
[0016] FIG. 4C is a perspective representation of another example
embodiment of the strip of pulp of FIG. 4A;
[0017] FIG. 5A is a schematic, top view of another example
embodiment of a strip of pulp;
[0018] FIG. 5B is a side view of the strip of pulp of FIG. 5A;
[0019] FIG. 5C is a perspective representation of the strip of pulp
of FIG. 5A;
[0020] FIG. 6 is a schematic, perspective representation of another
example embodiment of a strip of pulp;
[0021] FIG. 7 is a schematic, perspective representation of another
example embodiment of a strip of pulp;
[0022] FIG. 8 is a schematic, top view of another example
embodiment of a strip of pulp;
[0023] FIG. 9 is a schematic, perspective representation of another
example embodiment of a strip of pulp;
[0024] FIG. 10 is a schematic, perspective representation of
another example embodiment of a strip of pulp;
[0025] FIG. 11 is a schematic, perspective representation of
another example of a strip of pulp;
[0026] FIG. 12 is a schematic, perspective representation of
another example of a strip of pulp;
[0027] FIG. 13 is a schematic, side view of an example embodiment
of a mechanically entangled strip of pulp;
[0028] FIG. 14 is a schematic, side view of another example
embodiment of a mechanically entangled strip of pulp; and
[0029] FIG. 15 is a schematic, side view of an example embodiment
of an interleaved strip of pulp.
DETAILED DESCRIPTION
[0030] Various non-limiting embodiments of the present disclosure
will now be described to provide an overall understanding of the
principles of the process as disclosed herein. One or more examples
of these embodiments are illustrated in the accompanying drawings.
Those of ordinary skill in the art will understand that the process
for making an absorbent component from individual sheets of pulp as
described herein and the accompanying drawings are non-limiting
embodiments and that the scope of the various embodiments of the
present disclosure are defined solely by the claims. The features
illustrated or described in connection with one embodiment can be
combined with the features of other embodiments. Such modifications
and variations are intended to be included within the scope of the
present disclosure.
Definitions
[0031] Non-limiting examples of processes for making absorbent
components include known wet-laid papermaking processes and
air-laid papermaking processes. Such processes typically include
steps of preparing a fiber composition in the form of a suspension
in a medium, either wet, more specifically aqueous medium, or dry,
more specifically gaseous, i.e. with air as a medium. The aqueous
medium used for wet-laid processes is oftentimes referred to as a
fiber slurry. The fibrous slurry is then used to deposit a
plurality of fibers onto a forming wire or belt such that an
embryonic absorbent component is formed, after which drying and/or
bonding the fibers together results in a absorbent component.
Further processing the absorbent component may be carried out such
that a finished absorbent component is formed. For example, in
typical processes, the finished absorbent component is the
absorbent component that is wound on a reel at the end of the
process, and may subsequently be converted into a finished product,
e.g. an absorbent article.
[0032] "Fiber" as used herein means an elongate particle having an
apparent length greatly exceeding its apparent width, i.e. a length
to diameter ratio of at least about 10. A "fiber" is an elongate
particle as described above that exhibits a length of less than
5.08 cm (2 in.). Fibers are typically considered discontinuous in
nature. Non-limiting examples of fibers include natural fibers
including cotton, wood pulp (such as bleached kraft softwood or
hardwood), flax, hemp, peat moss, abaca, bamboo, eucalyptus,
bagasse, milkweed fluff, wheat straw, kenaf, and rayon.
[0033] In an illustration of one embodiment, "fiber" refers to
cellulosic fibers commonly known as wood pulp fibers. Applicable
wood pulps include chemical pulps, such as Kraft, sulfite, soda,
and sulfate pulps, as well as mechanical pulps including, for
example, groundwood, thermomechanical pulp and chemically modified
thermomechanical pulp. Chemical pulps, however, may be preferred
since they impart a superior tactile sense of softness to tissue
sheets made therefrom. Pulps derived from both deciduous trees
(hereinafter, also referred to as "hardwood") and coniferous trees
(hereinafter, also referred to as "softwood") may be utilized. The
hardwood and softwood fibers can be blended, or alternatively, can
be deposited in layers to provide a stratified web. U.S. Pat. No.
4,300,981 and U.S. Pat. No. 3,994,771 are incorporated herein by
reference for the purpose of disclosing layering of hardwood and
softwood fibers. Also applicable to an embodiment are fibers
derived from recycled paper, which may contain any or all of the
above categories as well as other non-fibrous materials such as
fillers and adhesives used to facilitate the original
papermaking.
[0034] In addition to the various wood pulp fibers, other
cellulosic fibers such as cotton linters, rayon, lyocell, and
bagasse can be used in an embodiment. Other sources of cellulose in
the form of fibers or capable of being spun into fibers include
grasses and grain sources.
[0035] "Pulp sheet" as used herein means a composite of individual
pulp fibers that have been arranged together as a result of a
pulping process. In one example, as is known by those of ordinary
skill in the art, a bale of pulp comprises multiple individual pulp
sheets in a stack. A pulping process is any process by which plant
material (wood, grass, straw etc.) is reduced to a fibrous mass. It
is achieved by rupturing bonds within plant structures. It can be
accomplished mechanically, thermally, chemically or some
combinations of these treatments. For avoidance of doubt, clearly
low density (for example less than 0.15 g/cm.sup.3) fibrous
structures, such as fibrous structures produced by a papermaking
process (individual plies thereof or finished products) used in
bath tissue, paper towels, and/or facial tissue, are not considered
pulp sheets for purposes of the present invention.
[0036] "Attach" and/or "attaching" as used herein means connecting
(for example, joining, linking and/or fastening together) two or
more materials, such as two or more individual pulp sheets
together. Further, attach and/or attaching means connecting by more
than surface frictional engagement due to normal forces experienced
between adjacent surfaces of two materials disposed in overlapping
relation. In one example, the attached two or more individual pulp
sheets are connected together such that separation of the
individual pulp sheets from one another by forces applied by a
defiberizer upon the connected individual pulp sheets is prevented.
In one example, two or more individual pulp sheets that are
attached to one another resist separating from one another when the
forces applied by a defiberizer in the machine direction are
greater than about 0.1 kgf (kilogram force) and/or greater than
about 0.5 kgf and/or greater than about 1 kgf and/or greater than
about 2 kgf and/or greater than about 5 kgf and/or greater than
about 10 kgf.
[0037] "Machine Direction" or "MD" as used herein means the
direction parallel to the flow of the pulp sheet into the
defiberizer. The machine direction is typically parallel to the
movement of any transfer device that transfers and/or transports a
pulp sheet and/or strip of pulp to a defiberizer. More
specifically, the MD means the direction in which an individual
sheet of pulp is transferred from a stack of pulp sheets to an
inlet of a defiberizer. In one example, one or more pulp sheets
enter the inlet of the defiberizer in the machine direction of the
defiberizer.
[0038] "Cross Machine Direction" or "CD" as used herein means the
direction perpendicular to the MD.
[0039] As used herein, the articles "a" and "an" when used herein,
for example, "an anionic surfactant" or "a fiber" is understood to
mean one or more of the material that is claimed or described.
[0040] All percentages and ratios are calculated by weight unless
otherwise indicated. All percentages and ratios are calculated
based on the total composition unless otherwise indicated.
Process for Making Absorbent Component
[0041] Referring to FIGS. 1-4, a process may comprise using an
apparatus 10 configured for defiberizing pulp from a stack of pulp
sheets 24, and forming an absorbent component 70, for example an
air-laid absorbent component 70, by depositing the defiberized pulp
onto a forming surface 28, which for example may be a fabric or
patterned belt. The stack of pulp sheets 24 may be made up of a
plurality of individual pulp sheets 14, wherein an individual pulp
sheet 14 may have a thickness, t, of greater than 0.1 mm and/or
greater than 0.5 mm and/or greater than 1 mm and/or greater than 2
mm and/or to about 20 mm and/or to about 15 mm and/or to about 10
mm and/or to about 6 mm In one embodiment, an individual pulp sheet
14 has a thickness in the range of about 3 mm to about 4 mm,
including all 0.1 mm increments within the recited range, as shown
in FIG. 3. An individual pulp sheet 14 can also have a thickness in
the range of about 0.5 mm to about 5 mm, a width in the range of
about 250 mm to about 1200 mm, and a height in the range of about
500 mm to about 1000 mm The stack of pulp sheets 24 may be
positioned in proximity of a destacker 12. The individual pulp
sheets 14 may be stacked in vertical, horizontal, or angled
arrangement to one another, as shown in FIGS. 2A-2C respectively.
The destacker 12 acts on one or more individual pulp sheets 14. The
destacker 12 may comprise, for example, a suctioning device,
clamping device, or other suitable device that removes one or more
individual pulp sheets 14 from the stack of pulp sheets 24. The
destacker 12 may then deposit the individual pulp sheet 14 on a
transfer device 34, such as a conveyor, carrier, belt, or other
device suitable for transferring an individual pulp sheet 14 up to
or through a series of processes. In one embodiment, a motor may
mechanically drive the transfer device 34. For example, the
transfer device 34 may be a conveyor, as is known in the art,
having two generally parallel sides, which are typically parallel
to the MD and a generally flat planar surface 35 on which the
individual pulp sheets may be deposited and moved along the MD
toward a defiberizer 22. For example, an individual pulp sheet 14
may be positioned so that a first face 36 of the individual pulp
sheet 14, as shown in FIG. 3, lays substantially flat on a
generally flat planar surface 35 of the transfer device 34 as shown
in FIG. 1; that is, a plane of the first face 36 of an individual
pulp sheet 14 may be positioned substantially parallel to a plane
of the surface of the transfer device 34. In an additional
embodiment, for example, the individual pulp sheet 14 may be
positioned, at least at some time prior to entering the defiberizer
22, so that the first face 36 is substantially perpendicular to or
in angled relation to the generally flat planar surface 35 of the
transfer device 34.
[0042] In one embodiment, as shown in FIG. 1, a subsequent
individual pulp sheet 14 may be removed from the stack of pulp
sheets 24 by the destacker 12 and deposited on the transfer device
34. This subsequent individual pulp sheet 14, referred to as a
second individual pulp sheet 48, may be placed on the transfer
device 34 in contact (such as in an overlapping relationship and/or
an abutting relationship) with a first individual pulp sheet 46
already present on the transfer device 34. The first individual
pulp sheet 46 and second individual pulp sheet 48 may be in contact
with each other and/or subsequent and/or preceding individual pulp
sheets 14 in a variety of ways, each of which facilitates
attachment of two or more individual pulp sheets 14, for example,
the first individual pulp sheet 46 and the second individual pulp
sheet 48. Further to the above, for example, a second individual
pulp sheet 48 may be positioned such that there exists an overlap
portion 40 between a face 36 or 42 of a first individual pulp sheet
46 and a face 36 or 42 of a second individual pulp sheet 48, as
shown in FIGS. 1, 4A-4C, 5A-5C, and 6. In an additional example
embodiment, as shown in FIGS. 1 and 7, a first individual pulp
sheet 46 and a second individual pulp sheet 48 may be positioned in
contact with one another such that at least one edge 38 of the
first individual pulp sheet 46 and at least one edge 38 of the
second individual pulp sheet 48 are in contact with one another
resulting in an abutted portion 44 between the adjacent pulp
sheets. The overlap portion 40 and/or abutted portion 44 may be
created by the rate at which the destacker 12 deposits the
individual pulp sheets 14 and/or by the use of other mechanical
devices such as a photo eye or trigger device as is known to those
of ordinary skill in the art. In addition, the overlap portion 40
and/or abutted portion 44 may be the result of manually positioning
the first individual pulp sheet 46 and the second individual pulp
sheet 48 on a surface of a transfer device 34.
[0043] In one embodiment, as shown in FIG. 1, a first individual
pulp sheet 46 and a second individual pulp sheet 48 are positioned
on the transfer device 34 in contact with at least a portion of one
another. A first individual pulp sheet 46 and a second individual
pulp sheet 48 each have the structural characteristics of an
individual pulp sheet 14 as shown in FIG. 3. Thus, the first
individual pulp sheet 46 and the second individual pulp sheet 48
both comprise at least one edge 38. In one embodiment, at least one
edge 38 of a first individual pulp sheet 46 and/or at least one
edge 38 of a second individual pulp sheet 48 may be substantially
parallel to the MD and/or the movement of the transfer device 34,
and at least one additional edge 38 of a first individual pulp
sheet 46 and/or at least one additional edge 38 of the second
individual pulp sheet 48 may be substantially perpendicular to the
MD and/or the movement of the transfer device 34. Examples of
various orientations of the first individual pulp sheet 46 and the
second individual pulp sheet 48 will be addressed in more detail
below.
[0044] In one embodiment, the transfer device 34 may move the first
individual pulp sheet 46 and the second individual pulp sheet 48 so
that the overlap portion 40 and/or abutted portion 44 pass through
an attaching operation comprising, for example an attaching
mechanism 16 capable of attaching the first individual pulp sheet
46 to one or more second individual pulp sheets 48. Non-limiting
examples of attaching operations comprise subjecting the overlap
portion 40 and/or abutted portion 44 to a crimping,
needle-punching, sewing, and/or embossing operation. The attaching
operation may include mechanically attaching adjacent individual
pulp sheets and/or adhering adjacent individual pulp sheets
together. Non-limiting examples of a mechanical attachment, which
will be addressed in more detail below, may comprise sewing,
dovetailing, mechanically entangling, and interleaving.
[0045] As shown in the FIG. 1, in one embodiment, a first
individual pulp sheet 46 may be attached to one or more second
individual pulp sheets 48 to form a strip of pulp 18. The strip of
pulp 18 is fed into a defiberizer 22 that exerts a force, parallel
to the MD, on the strip of pulp 18. The strength of the attachment
between individual pulp sheets 14, or, more specifically, a first
individual pulp sheet 46 and one or more second individual pulp
sheets 48, which make up the strip of pulp 18, can withstand a
force greater than about 0.1 kgf (kilogram force) and/or greater
than about 0.5 kgf and/or greater than about 1 kgf and/or greater
than about 2 kgf and/or greater than about 5 kgf and/or greater
than about 10 kgf.
[0046] In one embodiment, for example, the apparatus 10 shown in
FIG. 1 may comprise a sheet feeder 20, which may be used to
facilitate the movement of a strip of pulp 18 from a transfer
device 34 into a defiberizer 22. In addition to the transfer device
34, the strip of pulp 18 may be fed by a series of drive rollers,
or other equivalent drive mechanism (not shown), into a sheet
feeder 20. The drive rollers (not shown) may interact with the
strip of pulp 18 on the side opposite the transfer device 34 to
ensure the strip of pulp 18 enters the sheet feeder 20 in the
desired configuration. The sheet feeder 20 may comprise one or more
rollers 21 that contact and drive the strip of pulp 18 along the MD
toward the defiberizer 22.
[0047] In one embodiment, as shown in FIG. 1, the apparatus 10
comprises a defiberizer 22, such as a hammermill, disk mill, or
other apparatus for separating fibers to form defiberized fibers 26
from an individual pulp sheet 14 and/or a strip of pulp 18. A
non-limiting example of a suitable defiberizer 22 is a hammermill.
An example of a suitable hammermill is commercially available from
Oerlikon Neumag and Dan-Web.
[0048] In one embodiment, a strip of pulp 18 as shown in FIG. 4A,
for example, allows pulp to be continually fed into an inlet 32 of
a defiberizer 22. The constant feed of pulp allows the defiberizer
22 to produce a continuous flow of defiberized fibers 26 that may
be subsequently discharged in a stream of air passing through an
outlet 30 of the defiberizer 22. The defiberized fibers 26 are then
deposited onto a forming surface 28 to form an absorbent component
70. The deposition of the defiberized fibers 26 onto the forming
surface 28 may be aided by a vacuum device (not shown) located
under the forming surface 28.
[0049] The resulting absorbent component 70, such as an absorbent
core material, can have a basis weight of from about 50 to about
1000 grams per square meter, preferably from about 60 to about 800
grams per square meter, and more preferably from about 70 to about
700 grams per square meter.
[0050] The resulting absorbent component 70 can then be
incorporated into an absorbent article (not shown), such as a
diaper or feminine hygiene article, including adult incontinence
products and catamenial products such as tampons, sanitary napkins,
pantiliners, interlabial products, and the like. In one aspect, the
present invention further relates to an absorbent article
comprising a topsheet, a backsheet, and an absorbent component
therebetween, the absorbent component being made according to the
process of the present invention.
[0051] The process according to the present disclosure is
preferably a continuous process. Such a continuous process is
typically carried out at a relatively high rate of speed. The
continuous process can be conducted at a speed of at least about 2
meters of fibrous material per minute, preferably at least about 10
meters of fibrous material per minute, and more preferably at least
about 20 meters of fibrous material per minute.
[0052] The process of the present disclosure further encompasses a
process wherein more than one outlet is utilized to form the
absorbent component, such as two or three separate outlets.
[0053] The process of the present disclosure further encompasses a
process wherein more than one defiberizer is utilized to provide
defiberized fibers to an individual outlet, such as two, three or
four defiberizers per outlet.
[0054] The process for making an absorbent component according to
the present disclosure is preferably an air-laid process.
Strip of Pulp
[0055] A strip of pulp 18 may be configured in numerous ways. The
following discusses various example embodiments for a strip of pulp
18. As discussed above, the individual pulp sheets 14 that create a
strip of pulp 18 may be attached by an adhesive or mechanical
attachment. A strip of pulp 18 may vary in thickness along its
dimensions or it may be of relatively uniform thickness across its
dimensions depending on the desired configuration of the individual
pulp sheets 14. A variation in thickness of a strip of pulp 18 may
result in a defiberizer 22 producing a variable volume of
defiberized fibers 26, but the defiberizer 22 can still produce a
substantially continuous flow of defiberized fibers 26 thereby
avoiding any interruptions in the substantially continuous flow of
defiberized fibers 26 exiting the defiberizer 22 via the outlet 30.
In addition, in one embodiment, the width of the strip of pulp 18
in the CD should not exceed the width in the CD of the inlet 32 of
the defiberizer 22.
[0056] In one embodiment, referring to FIGS. 4A-4C, a strip of pulp
18 may be assembled from one or more individual pulp sheets 14. A
strip of pulp 18 may be assembled such that at least a portion of a
second individual pulp sheet 48 is positioned on at least a portion
of a first individual pulp sheet 46, and at least a portion of a
third individual pulp sheet 50 is positioned on at least a portion
of the second individual pulp sheet 48. More specifically, at least
a portion of the second face 42 of the second individual pulp sheet
48 may overlap and be attached to at least a portion of the first
face 36 of the first individual pulp sheet 46, and at least a
portion of the second face 42 of the third individual pulp sheet 50
may overlap and be attached to at least a portion of the first face
36 of the second individual pulp sheet 48, as shown in FIGS. 4B and
4C. In one embodiment, a face 36 or 42 of one individual pulp sheet
14 overlaps less than 80% and/or less than 50% and/or less than 30%
and/or less than 20% and/or less than 10% and/or less than 5%
and/or less than 1% and/or 0% of the surface area of a face 36 or
42 of another individual pulp sheet 14. In another embodiment,
adjacent first and second individual pulp sheets 46 and 48,
respectively, have an overlap portion 40 that facilitates the
attachment of the first individual pulp sheet 46 with the second
individual pulp sheet 48. An overlap portion 40 is not necessary to
attach individual sheets of pulp but is rather one example
embodiment.
[0057] In one embodiment, as shown in FIG. 4C, adjacent individual
pulp sheets 14 may be positioned such that at least one edge 38 of
a first individual pulp sheet 46 and at least one edge 38 of a
second individual pulp sheet 48 are in staggered relation to one
another. Stated another way, at least one edge 38 of the first
individual pulp sheet 46 may be substantially parallel to both the
MD and at least one edge 38 of the second individual pulp sheet 48,
and at least one edge 38 of the first individual pulp sheet 46 and
at least one edge 38 of the second individual pulp sheet 48 are not
coplanar. The plane of an edge 38 of the first individual pulp
sheet 46 and the second individual pulp sheet 48 may be
substantially perpendicular to an edge 38 of the first individual
pulp sheet 46 and the second individual pulp sheet,
respectively.
[0058] In one embodiment, referring to FIGS. 5A-5C, a strip of pulp
18 may be assembled by attaching one or more individual pulp sheets
14 such that a second individual pulp sheet 48 is positioned on at
least a portion of both a first individual pulp sheet 46 and a
third individual pulp sheet 50. More specifically, at least a
portion of the second face 42 of the second individual pulp sheet
48 may be attached to at least a portion of the first face 36 of at
least one of the first individual pulp sheet 46 and a third
individual pulp sheet 50, as shown in FIGS. 5B and 5C. Referring to
FIG. 5B, in one example embodiment, a first individual pulp sheet
46 may be separated by a distance, d, from a third individual pulp
sheet 50. The distance, d, may be less than or equal to the length
of the longest at least one edge 38 of the second individual pulp
sheet 48. If, for example, in one embodiment the distance, d, was
zero, the first individual pulp sheet 46 would abut the third
individual pulp sheet 50. If, for example, in one embodiment, the
distance, d, was equal to the length of at least one edge 38 of the
second individual pulp sheet 48, least one edge 38 of the first
individual pulp sheet 46 would abut at least one edge 38 of the
second individual pulp sheet 48 and least one edge 38 of the third
individual pulp sheet 50 would abut another at least one edge 38 of
the second individual pulp sheet 48. In various embodiments, the
distance, d, may be any distance less than or equal to the length
of the longest edge 38 of an individual sheet of pulp in any 0.1
inch increment. In addition, in one embodiment, the overlap portion
40 may be equivalent to the length of at least one edge 38
subtracted from the distance, d, between the first individual pulp
sheet 46 and the third individual pulp sheet 50. The overlap
portion 40 may be a single overlap portion 40 or multiple overlap
portions 40. If there is more than a single overlap portion 40, the
overlap portion 40 created by the first individual pulp sheet 46
and the second individual pulp sheet 48 may be equal to or unequal
to the overlap portion 40 created by the second individual pulp
sheet 48 and the third individual pulp sheet 50.
[0059] In one embodiment, referring to FIG. 6, a strip of pulp 18
may be assembled from two or more individual pulp sheets 14 such
that the strip of pulp 18 may have a relatively uniform thickness
of two or more individual pulp sheets 14. The strip of pulp 18 may
be assembled such that a first individual pulp sheet 46 is placed
in contiguous relation to or abuts and attaches to a third
individual pulp sheet 50, and the second face 42 of the second
individual pulp sheet 48 overlaps and attaches to at least a
portion of the first face 36 of at least one of the first
individual pulp sheet 46 and the third individual pulp sheet 50.
More specifically, at least a portion of the second face 42 of the
second individual pulp sheet 48 may be placed on at least a portion
of the first face 36 of the first individual pulp sheet 46 and the
third individual pulp sheet 50, and at least a portion of at least
one edge 38 of the first individual pulp sheet 46 abuts at least a
portion of at least one edge 38 of a third individual pulp sheet
50. Individual pulp sheets 14 adjacent to the strip of pulp 18
configuration, as described above, may abut at least a portion of
at least one edge 38 of the second individual pulp sheet 48 and/or
the third individual pulp sheet 50. In an alternate embodiment, the
strip of pulp 18 may be formed such that individual pulp sheets 14
adjacent to the strip of pulp 18 configuration, as previously
disclosed, are spaced some distance, d, apart such that at least
one edge 38 of the second individual pulp sheet 48 is not
interacted with by an adjacent individual pulp sheet 14 and/or at
least one edge 38 of the third individual sheet 50 is not
interacted with by an adjacent individual pulp sheet 14.
[0060] In one embodiment, referring to FIG. 7, a strip of pulp 18
of relatively uniform thickness may be assembled from two or more
individual pulp sheets 14. The strip of pulp 18 may be assembled
such that at least one edge 38 of a first individual pulp sheet 46
abuts and attaches to at least a portion of at least one edge 38 of
a second individual pulp sheet 48 to form an abutted portion 44,
and at least one edge 38 of a second individual pulp sheet 48 abuts
and attaches to at least a portion of at least one edge 38 of a
third individual pulp sheet 50 to form an abutted portion 44. In
one embodiment, at least one edge 38 of a first individual pulp
sheet 46 may be substantially planar to at least one edge 38 of a
second individual pulp sheet 48 and at least one edge 38 of a third
individual pulp sheet 50.
[0061] In one embodiment, referring to FIG. 8, a strip of pulp 18
may be configured such that the individual sheets of pulp 18 are
attached in angled relation to one another. In one example
embodiment, a strip of pulp 18 may be assembled such that at least
one edge 38 of a first individual pulp sheet 46 and/or a second
individual pulp sheet 48 and/or a third individual pulp sheet 50 is
placed at an angle to the MD. More specifically, at least one edge
38 of a first individual pulp sheet 46 and/or a second individual
pulp sheet 48 and/or a third individual pulp sheet 50 forms an
angle of greater than about 5 degrees and/or greater than about 15
degrees and/or greater than about 30 degrees and/or greater than
about 45 degrees and/or greater than about 60 degrees and/or
greater than about 75 degrees and/or equal to about 90 degrees. In
another example embodiment, a second individual pulp sheet 48 may
abut or overlap at least a portion of first individual pulp sheet
46 and a third individual pulp sheet 50. More specifically, a first
individual pulp sheet 46 may form an overlap portion 40 with a
second individual pulp sheet 48, and a second individual pulp sheet
48 may form an abutted portion 44 with a third individual pulp
sheet 50.
[0062] In one embodiment, referring to FIGS. 9 and 10, adjacent
individual pulp sheets 14 may be configured such that at least a
portion of each individual pulp sheet 14 is in contact with another
individual pulp sheet 14. As shown in FIG. 9, for example, at least
a portion of at least one edge 38 of a first individual pulp sheet
46 may abut and attach to at least a portion of at least one edge
38 of a second individual pulp sheet 48. In another embodiment, a
first individual pulp sheet 46 may overlap and attach to at least a
portion of a second individual pulp sheet 48. In an alternate,
example embodiment, a third individual pulp sheet 50 may abut and
attach to at least one edge 38 of the first individual pulp sheet
46 and/or at least one edge 38 of the second individual pulp sheet
48. In still another example embodiment, a third individual pulp
sheet 50 may overlap and attach to at least a portion of the first
individual pulp sheet 46 and/or the second individual pulp sheet
48.
[0063] As shown in FIG. 10, individual pulp sheets 14 having two or
more edges 38 that may not be of equal length may be assembled to
form a strip of pulp 18. For example, a first individual pulp sheet
46 may be positioned such that one or more of its longer edges 38
contacts at least a portion of a second individual pulp sheet's 48
one or more shorter edges 38 and vice versa. Depending on the
length of the longer edge 38 of the first individual pulp sheet 46,
one or more second individual pulp sheets 48 may abut the longer
edge 38 of the first individual pulp sheet 46. In another example
embodiment, one or more of the second individual pulp sheets 48 may
overlap the first individual pulp sheet 46.
[0064] In one embodiment, referring to FIGS. 11 and 12, two or more
strips of pulp 18 may be combined together to form a combined strip
of pulp 56. For example, a combined strip of pulp 56 comprising a
first strip of pulp 18 and one or more second strips of pulp 54,
which may be attached to one another, may be fed into a defiberizer
22.
[0065] In one embodiment, one or more strips of pulp 18 may be
assembled on different process lines and subsequently transferred
to a common transfer device 34. For example, a first individual
pulp sheet 46 may be attached to one or more second individual pulp
sheets 48 to form a strip of pulp 18. In addition, a third
individual pulp sheet 50 may be attached to one or more fourth
individual pulp sheets 52 to form one or more second strips of pulp
54. The strip of pulp 18 and the one or more second strips of pulp
54 may be formed independently of one another and transferred to a
common position, such as on a transfer device 34. The strip of pulp
18 may be positioned on at least a portion of one or more second
strips of pulp 54 to form a combined strip of pulp 56. In one
embodiment, the strip of pulp 18 may not be attached to one or more
second strips of pulp 54 to form the combined strip of pulp 56. In
another embodiment, the strip of pulp 18 may be attached to one or
more second strips of pulp 54 to form the combined strip of pulp
56. In another example embodiment, the combined strip of pulp 56
may be formed such that at least one edge 38 of the strip of pulp
18 is substantially parallel to both the MD and at least one edge
38 of one or more second strips of pulp 54. In an example
embodiment, the combined strip of pulp 56 may be formed such that
at least one edge 38 of the strip of pulp 18 is substantially
planar to at least one edge 38 of one or more second strips of pulp
54. In various embodiments, the combined strip of pulp 56 may have
a thickness greater than two individual pulp sheets 14. The strip
of pulp 18 and one or more second strips of pulp 54 may be formed
in any of the previously discussed configurations and any
additional configuration that would be known to one of ordinary
skill in the art.
[0066] The attaching operation may include mechanically attaching
adjacent individual pulp sheets and/or adhering adjacent individual
pulp sheets together. Non-limiting examples of a mechanical
attachment may comprise sewing, dovetailing, mechanically
entangling, and/or interleaving.
[0067] In one embodiment, mechanically attaching comprises sewing.
Sewing a first individual pulp sheet 46 to one or more second
individual pulp sheets 48 may involve additional material such as a
piece of thread. Such additional material may be present throughout
a defiberizing process and ultimately in a product. In one
embodiment, the additional material used for attaching the sheets
of pulp is of a structure and/or characteristic so as to avoid
creating clumping issues in the defiberizer 22 and/or discrepancies
and/or defects in a product, such as a absorbent component,
incorporating the defiberized fibers 26. Clumping, generally,
refers to a dense group or groups of fibers that become entangled
in the defiberizer 22. Clumping is generally undesirable for paper
products, such as facial tissue, paper towels, and bath tissue,
because clumps may lead to inconsistencies in properties and/or
visible variations in a product, such as a absorbent component,
incorporating the defiberized fibers 26. In addition, the
additional material should minimize changes in the quality or
characteristics of the product. In one embodiment, the additional
material used to attach the individual pulp sheets 14 may comprise,
for example, a dissolvable thread or a fibrous thread as commonly
used in industrial sewing applications, such as nylon,
polypropylene and/or cellulose, for example cotton.
[0068] In one embodiment, the individual pulp sheets 14 may be
attached by mechanically entangling as shown in FIGS. 13 and 14. In
one embodiment, a first individual pulp sheet 46 overlaps at least
a portion of one or more second individual pulp sheets 48, and the
overlap portion 40 may be mechanically entangled to attach a first
individual pulp sheet 46 to one or more second individual pulp
sheets 48. In one embodiment, mechanically entangling may comprise
deforming at least a portion of or a localized area of the first
individual pulp sheet 46. One or more second individual pulp sheets
48 may be deformed, either concurrently or subsequent to the first
individual pulp sheet 46, to substantially match the deformation of
the first individual pulp sheet 46 such that the first individual
pulp sheet 46 fits within the one or more second individual pulp
sheets 48. The localized deformations in at least one of the first
face 36 and the second face 42 of the first individual pulp sheet
46 and one or more second individual pulp sheets 48 may be used to
attach the first individual pulp sheet 46 to the one or more second
individual pulp sheets 48. In another embodiment, the one or more
localized deformations in the first individual pulp sheet 46 and
the one or more second individual pulp sheets 48 may be different,
as shown in FIG. 14. The attachment of the first individual pulp
sheet 46 to the one or more second individual pulp sheets 48 may
withstand the force, which is parallel to the MD, the defiberizer
22 exerts on the first individual pulp sheet 46. Thus, the one or
more second individual pulp sheets 48 remain attached to the first
individual pulp sheet 46 as the strip of pulp 18 is fed into the
defiberizer 22. The first individual pulp sheet 46 and the one or
more second individual pulp sheets 48 may be mechanically
entangled, for example, by feeding the overlap portion 40 through
an embossing operation.
[0069] In one embodiment, attaching two or more individual pulp
sheets 14 together by adhering can comprise gluing and/or taping a
first individual pulp sheet 46 to one or more second individual
pulp sheets 48. Analogous to the above with respect to mechanically
attaching, the adhesive material (glue) may consist of a material
which avoids creating clumping issues in the defiberizer 22 and/or
discrepancies and/or defects in a product, such as a absorbent
component, incorporating the defiberized fibers 26 for the same
reasons described above. In addition, the adhesive material should
minimize changes in the quality or characteristics of the product.
Non-limiting examples of adhering may comprise taping and gluing.
In one embodiment, two or more individual pulp sheets may be
attached together by tape. A non-limiting example of a suitable
tape is commercially available from 3M or Anchor Continental. In
another embodiment, two or more individual pulp sheets 14 may be
attached together by a glue, for example a water-based glue.
Non-limiting examples of suitable glues are commercially available
from H. B. Fuller under the trade names WB-4955M, WB-4989 and
WB-4997, Henkel under the brand name Adhesin.RTM. and National
Starch & Chemical Company.
[0070] In one embodiment, the individual pulp sheets 14 may be
attached by interleaving a first individual pulp sheet 46 with one
or more second individual pulp sheets 48 and a third individual
pulp sheet 50, as shown in FIG. 15. Each of a first individual pulp
sheet 46, a second individual pulp sheet 48, and a third individual
pulp sheet 50 may be placed in a C-shaped configuration and
interleaved to prevent the separation along the MD of the first
individual pulp sheet 46 from the second individual pulp sheet 48
and the third individual pulp sheet 50. The interleaving may be
performed manually or by a machine. In one embodiment, to assemble
the individual pulp sheets 14 in an interleaving configuration, a
first individual pulp sheet 46 may be bent such that a cavity 59 is
formed between the at least one end 58 and at least a portion of a
face 36 or 42 of the first individual pulp sheet 46. Further, each
end 58 may be separated from one another by a gap, g. The gap, g,
may be large enough to accept at least a portion of at least one
and/or two and/or more individual pulp sheets 14. A second
individual pulp sheet 48 may be bent in a similar C-shaped
configuration as the first individual pulp sheet 46. The second
individual pulp sheet 48 may be rotated opposite the first
individual pulp sheet 46. An end 58 of the second individual pulp
sheet 48 may be inserted into the gap g of the first individual
pulp sheet 46 such that the second individual pulp sheet 48
substantially surrounds at least a portion of one end 58 of the
first individual pulp sheet 46. A third individual pulp sheet 50
may be bent in a similar C-shaped configuration as both the first
individual pulp sheet 46 and the second individual pulp sheet 48.
The second individual pulp sheet 48 substantially surrounds at
least a portion of an end 58 of the third individual pulp sheet 50.
The first individual pulp sheet 46 may be interleaved with the
second individual pulp sheet 48 and the third individual pulp sheet
50 to form a strip of pulp 18. In one embodiment, the strip of pulp
18 may have a substantially uniform thickness. In another
embodiment, the bend 60 and each end 58 of the first individual
pulp sheet 46 may be substantially perpendicular to the MD. Thus, a
defiberizer 22 may exert a force on the first individual pulp sheet
46 that is substantially perpendicular to the bend 60 of the first
individual pulp sheet 46.
[0071] In one embodiment, two or more pulp sheets are attached to
one another using a material that is acceptable for inclusion in a
product into which the defiberized fibers 26 are ultimately
incorporated.
[0072] In another embodiment, the attaching operation comprises a
step of controlling the moisture level of the pulp sheets prior to
and/or during and/or post the attaching operation. In one
embodiment, the moisture level of the pulp sheets prior to and/or
during the attaching operation is greater than 5% and/or greater
than 6% and/or greater than 8% and/or greater than 10% by weight of
the pulp sheet.
[0073] In another embodiment, the strip of pulp 18 may be assembled
with multiple attachments. For example, the first individual pulp
sheet 46 may be adhered to the one or more second individual pulp
sheets 48, and the one or more second individual pulp sheets 48 may
be mechanically attached to the third individual pulp sheet 50.
More specifically, the first individual pulp sheet 46 may be glued
to the one or more second individual pulp sheets 48, and the one or
more second individual pulp sheets 48 may be sewn to the third
individual pulp sheet 50. Any type of attachment as described above
may be used in conjunction with other types of attachment to
assemble a strip of pulp 18.
[0074] The dimensions and values disclosed herein are not to be
understood as being strictly limited to the exact numerical values
recited. Instead, unless otherwise specified, each such dimension
is intended to mean both the recited value and a functionally
equivalent range surrounding that value. For example, a dimension
disclosed as "40 mm" is intended to mean "about 40 mm."
[0075] Every document cited herein, including any cross referenced
or related patent or application, is hereby incorporated herein by
reference in its entirety unless expressly excluded or otherwise
limited. The citation of any document is not an admission that it
is prior art with respect to any invention disclosed or claimed
herein or that it alone, or in any combination with any other
reference or references, teaches, suggests or discloses any such
invention. Further, to the extent that any meaning or definition of
a term in this document conflicts with any meaning or definition of
the same term in a document incorporated by reference, the meaning
or definition assigned to that term in this document shall
govern.
[0076] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
* * * * *